Vehicle and vehicle step apparatus with multiple drive motors

ABSTRACT

A vehicle step apparatus comprises a first extending and retracting device comprising a first mounting bracket, a first step bracket, and a first arm assembly configured to drive the first step bracket to move between a first extended position and a first retracted position; a second extending and retracting device comprising a second mounting bracket, a second step bracket, and a second arm assembly configured to drive the second step bracket to move between a second extended position and a second retracted position; a step mounted on the first and second step bracket; a first permanent magnet direct current motor mounted on the first mounting bracket and coupled with the first arm assembly to drive the first arm assembly; and a second permanent magnet direct current motor mounted on the second mounting bracket and coupled with the second arm assembly to drive the second arm assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of and claims priority to andall benefits of U.S. patent application Ser. No. 16/655,149, filed Oct.16, 2019, now U.S. Pat. No. 10,618,472 B2, which is acontinuation-in-part of and claims priority to and all benefits of U.S.patent application Ser. No. 15/200,940, filed Jul. 1, 2016, now U.S.Pat. No. 10,479,278, which claims priority to and all benefits ofChinese Patent Application 201510731518.7 filed on Oct. 30, 2015,Chinese Patent Application 201520860004.7 filed on Oct. 30, 2015,Chinese Patent Application 201510468824.6 filed on Aug. 4, 2015, ChinesePatent Application 201520576675.0 filed on Aug. 4, 2015, Chinese PatentApplication 201510469324.4 filed on Aug. 4, 2015, and Chinese PatentApplication 201520580148.7 filed on Aug. 4, 2015, all of which arehereby expressly incorporated herein by reference in their entirety.

TECHNICAL FIELD

Embodiments of the present technology generally relate to the field ofvehicle accessories, and more particularly, to a vehicle and a vehiclestep apparatus with multiple drive motors.

BACKGROUND

In relative art, a vehicle step apparatus of a vehicle uses a drivingmechanism (with motor) and a driven mechanism (without motor) to drive astep to move. That is to say, the vehicle step apparatus uses one motorto drive the step to move. Thus, all of load is borne by the one motor,such that the load of the one motor is very high. Thus, a requirementfor performance of the one motor is very high, a manufacturingdifficulty, a manufacturing cost and a failure rate of the one motor areincreased and a working life of the one motor is shortened.

Moreover, because the driving mechanism has a function of self-lock andthe driven mechanism does not have a function of self-lock, the drivenmechanism is easy to droop, especially when the step is very long.

SUMMARY

The present technology seeks to solve at least one of the technicalproblems existing in the related art. Accordingly, a first aspect of thepresent technology provides a vehicle step apparatus.

A second aspect of the present technology provides a vehicle, whichincludes the above vehicle step apparatus.

Embodiments of a first aspect of the present technology provide avehicle step apparatus, including: a first extending and retractingdevice comprising a first mounting bracket, a first step bracket, and afirst arm assembly coupled between the first mounting bracket and thefirst step bracket and configured to drive the first step bracket tomove between a first extended position and a first retracted position; asecond extending and retracting device comprising a second mountingbracket, a second step bracket, and a second arm assembly coupledbetween the second mounting bracket and the second step bracket andconfigured to drive the second step bracket to move between a secondextended position and a second retracted position; a step mounted on thefirst step bracket and the second step bracket; a first permanent magnetdirect current motor mounted on the first mounting bracket and coupledwith the first arm assembly to drive the first arm assembly; and asecond permanent magnet direct current motor mounted on the secondmounting bracket and coupled with the second arm assembly to drive thesecond arm assembly.

With the vehicle step apparatus according to embodiments of the firstaspect of the present technology, the vehicle step apparatus is low inmanufacturing cost, low in failure rate, and long in working life, hasgood synchronization, and drooping of the vehicle step apparatus can beprevented.

Embodiments of a second aspect of the present technology provide avehicle, including: a first extending and retracting device comprising afirst mounting bracket, a first step bracket, and a first arm assemblycoupled between the first mounting bracket and the first step bracketand configured to drive the first step bracket to move between a firstextended position and a first retracted position; a second extending andretracting device comprising a second mounting bracket, a second stepbracket, and a second arm assembly coupled between the second mountingbracket and the second step bracket and configured to drive the secondstep bracket to move between a second extended position and a secondretracted position; a step mounted on the first step bracket and thesecond step bracket; a first permanent magnet direct current motormounted on the first mounting bracket and having a first motor shaftcoupled with the first arm assembly; and a second permanent magnetdirect current motor mounted on the second mounting bracket and having asecond motor shaft coupled with the second arm assembly.

The vehicle is low in manufacturing cost, low in failure rate, and longin working life.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial exploded view of a vehicle according to an exampleembodiment of the present technology;

FIG. 2 is a schematic view of a first extending and retracting deviceand a second extending and retracting device of a vehicle step apparatusaccording to an example embodiment of the present technology, in whichboth the first extending and retracting device and the second extendingand retracting device are in the form of four-link mechanism;

FIG. 3 is a schematic view of a first extending and retracting deviceand a second extending and retracting device of a vehicle step apparatusaccording to an example embodiment of the present technology, in whichboth the first extending and retracting device and the second extendingand retracting device are in the form of five-link mechanism;

FIG. 4 is a schematic view of a first extending and retracting deviceand a second extending and retracting device of a vehicle step apparatusaccording to an example embodiment of the present technology, in whichboth the first extending and retracting device and the second extendingand retracting device are in the form of six-link mechanism;

FIG. 5 is a schematic view of a vehicle step apparatus according to anexample embodiment of the present technology;

FIG. 6 is an exploded view of a vehicle step apparatus according to anexample embodiment of the present technology;

FIG. 7 is a partial exploded view of a vehicle step apparatus accordingto an example embodiment of the present technology;

FIG. 8 is a partial exploded view of a vehicle step apparatus accordingto an example embodiment of the present technology.

FIG. 9 is a schematic view of a vehicle step apparatus according to anexample embodiment of the present technology.

FIG. 10 is a schematic diagram of a self-locking motor assemblyaccording to an example embodiment of the present technology.

FIG. 11 is an exploded view of a self-locking motor assembly accordingto an example embodiment of the present technology.

FIG. 12 is a partial sectional view of a self-locking motor assemblyaccording to an example embodiment of the present technology, whichshows the interface between a worm reduction mechanism and a worm gear.

FIG. 13 is another partial sectional view of a self-locking motorassembly according to an example embodiment of the present technology,which shows the interface between a worm reduction mechanism and a wormgear.

DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the presenttechnology. Embodiments of the present technology will be shown indrawings, in which the same or similar members and the members havingsame or similar functions are denoted by like reference numeralsthroughout the descriptions. The embodiments described herein accordingto drawings are explanatory and illustrative, not construed to limit thepresent technology.

The following description provides a plurality of embodiments orexamples configured to achieve different structures of the presenttechnology. In order to simplify the publication of the presenttechnology, components and dispositions of the particular embodiment aredescribed in the following, which are only explanatory and not construedto limit the present technology. In addition, the present technology mayrepeat the reference number and/or letter in different embodiments forthe purpose of simplicity and clarity, and the repetition does notindicate the relationship of the plurality of embodiments and/ordispositions. Moreover, in description of the embodiments, the structureof the second characteristic “above” the first characteristic mayinclude an embodiment formed by the first and second characteristiccontacted directly, and also may include another embodiment formedbetween the first and the second characteristic, in which the firstcharacteristic and the second characteristic may not contact directly.

In the description of the present technology, unless specified orlimitation otherwise, it should be noted that, terms “mounted,”“coupled,” “coupled to,” and “coupled with” may be understood broadly,such as electronic connection or mechanical connection, innercommunication between two members, direct connection or indirectconnection via intermediary. Those having ordinary skills in the artshould understand the specific meanings in the present technologyaccording to specific situations.

At present, the vehicle industry is increasingly developing, and vehicledesign is becoming more and more detailed and humanized. For somevehicles with high chassis, it is quite difficult for passengers to geton and off, especially for the elderly, the weak, the sick and pregnantpassengers, who have difficulty getting on and off high chassis vehiclesby themselves.

In order to address these challenges and problems, conventional methodsin existing applications is to add a step (also referred to as a pedalor running board) to each passenger entry side of the vehicle. Someexamples include a fixed (non-moveable) pedal, whereas otherconventional methods include providing a moveable pedal, such as amanually retractable pedal or an electrically retractable pedal. Today,mainstream electric retractable steps in the market are driven by aone-sided single motor. Yet, a single drive motor requires high motorperformance, which results in high manufacturing difficulty and highcost.

In some aspects, a vehicle step apparatus and a vehicle having a vehiclestep apparatus in accordance with the disclosed embodiments aredescribed. A vehicle 1000 according to embodiments of the presenttechnology will be described with reference to the drawings.

As shown in FIGS. 1-6, the vehicle 1000 according to embodiments of thepresent technology includes a chassis 40 and a vehicle step apparatus100. The vehicle step apparatus 100 includes a first extending andretracting device 10 a, a second extending and retracting device 10 b, astep 20, a first permanent magnet direct current motor 30 a and a secondpermanent magnet direct current motor 30 b.

The first extending and retracting device 10 a includes a first mountingbracket 11 a, a first step bracket 12 a and a first arm assembly 13 a.The first arm assembly 13 a is coupled between the first mountingbracket 11 a and the first step bracket 12 a and configured to drive thefirst step bracket 12 a to move between a first extended position and afirst retracted position. The first mounting bracket 11 a is mounted onthe chassis 40.

The second extending and retracting device 10 b includes a secondmounting bracket 11 b, a second step bracket 12 b and a second armassembly 13 b. The second arm assembly 13 b is coupled between thesecond mounting bracket 11 b and the second step bracket 12 b andconfigured to drive the second step bracket 12 b to move between asecond extended position and a second retracted position. The secondmounting bracket 11 b is mounted on the chassis 40.

The step 20 is mounted on the first step bracket 12 a and the secondstep bracket 12 b. The first permanent magnet direct current motor 30 ais mounted on the first mounting bracket 11 a and coupled with the firstarm assembly 13 a to drive the first arm assembly 13 a. The secondpermanent magnet direct current motor 30 b is mounted on the secondmounting bracket 11 b and coupled with the second arm assembly 13 b todrive the second arm assembly 13 b.

In some embodiments, the first permanent magnet direct current motor 30a has a first motor shaft 32 a coupled with the first arm assembly 13 a.The second permanent magnet direct current motor 30 b has a second motorshaft 32 b coupled with the second arm assembly 13 b.

Thus, the first step bracket 12 a is driven to move between the firstextended position and the first retracted position by the firstpermanent magnet direct current motor 30 a via the first arm assembly 13a, and the second step bracket 12 b is driven to move between the secondextended position and the second retracted position by the secondpermanent magnet direct current motor 30 b via the second arm assembly13 b. In other words, the vehicle 1000 uses the first permanent magnetdirect current motor 30 a and the second permanent magnet direct currentmotor 30 b to drive the step 20 to extend and retract.

The vehicle 1000 uses two motors, i.e. the first permanent magnet directcurrent motor 30 a and the second permanent magnet direct current motor30 b, to drive the step 20 to extend and retract, thus a load applied tothe vehicle step apparatus 100 is distributed to the first permanentmagnet direct current motor 30 a and the second permanent magnet directcurrent motor 30 b.

Thus, comparing to the vehicle step apparatus 100 employing only onemotor, the load of the first permanent magnet direct current motor 30 ais decreased so as to decrease a failure rate of the first permanentmagnet direct current motor 30 a, and the load of the second permanentmagnet direct current motor 30 b is decreased so as to decrease afailure rate of the second permanent magnet direct current motor 30 b,thus prolonging a working life of the first permanent magnet directcurrent motor 30 a and a working life of the second permanent magnetdirect current motor 30 b.

Because the load of the first permanent magnet direct current motor 30 ais low, a requirement for performance of the first permanent magnetdirect current motor 30 a is decreased so as to lower a manufacturingdifficulty and a manufacturing cost of the first permanent magnet directcurrent motor 30 a.

Similarly, the load of the second permanent magnet direct current motor30 b is low, a requirement for performance of the second permanentmagnet direct current motor 30 b is decreased so as to lower amanufacturing difficulty and a manufacturing cost of the secondpermanent magnet direct current motor 30 b.

Because both the first permanent magnet direct current motor 30 a andthe second permanent magnet direct current motor 30 b have a function ofself-lock, even the step 20 is very long, both the first permanentmagnet direct current motor 30 a and the second permanent magnet directcurrent motor 30 b can be prevented from drooping.

Additionally, for the first permanent magnet direct current motor 30 aand the second permanent magnet direct current motor 30 b, a rotationalspeed is related to a load. Thus, a rotational speed of a motor will bedecreased due to an increasing load, and a rotational speed of a motorwill be increased due to a decreasing load.

Thus, a rotational speed of the first permanent magnet direct currentmotor 30 a is dynamically balanced with a rotational speed of the secondpermanent magnet direct current motor 30 b, so as to realize asynchronized motion of the first extending and retracting device 10 aand the second extending and retracting device 10 b.

Thus, the vehicle step apparatus 100 according to embodiments of thepresent technology is low in manufacturing cost, low in failure rate,long in working life, and has good synchronization, and the vehicle stepapparatus 100 can be prevented from drooping.

As shown in FIG. 1, in some embodiments, the vehicle 1000 includes thechassis 40 and the vehicle step apparatus 100. The vehicle stepapparatus 100 includes the first extending and retracting device 10 a,the second extending and retracting device 10 b, the step 20, the firstpermanent magnet direct current motor 30 a and the second permanentmagnet direct current motor 30 b.

The first extending and retracting device 10 a includes the firstmounting bracket 11 a, the first step bracket 12 a and the first armassembly 13 a. The first mounting bracket 11 a is mounted on the chassis40. The first step bracket 12 a is used to mount the step 20. The firstarm assembly 13 a is coupled between the first mounting bracket 11 a andthe first step bracket 12 a and configured to drive the first stepbracket 12 a to move between the first extended position and the firstretracted position.

The second extending and retracting device 10 b includes the secondmounting bracket 11 b, the second step bracket 12 b and the second armassembly 13 b. The second mounting bracket 11 b is mounted on thechassis 40. The second step bracket 12 b is used to mount the step 20.The second arm assembly 13 b is coupled between the second mountingbracket 11 b and the second step bracket 12 b and configured to drivethe second step bracket 12 b to move between the second extendedposition and the second retracted position.

Both the first mounting bracket 11 a and the second mounting bracket 11b may be mounted on the chassis 40 in well-known manner. The step 20 ismounted on the first step bracket 12 a and the second step bracket 12 bby known means.

As shown in FIG. 1, the first arm assembly 13 a includes a plurality ofarms pivotally connected together. At least one arm of the first armassembly 13 a is coupled with the first mounting bracket 11 a, and atleast one arm of the first arm assembly 13 a is coupled with the firststep bracket 12 a.

As shown in FIG. 1, the second arm assembly 13 b includes a plurality ofarms pivotally connected together. At least one arm of the second armassembly 13 b is coupled with the second mounting bracket 11 b, and atleast one arm of the second arm assembly 13 b is coupled with the secondstep bracket 12 b.

The first permanent magnet direct current motor 30 a is mounted on thefirst mounting bracket 11 a, and the second permanent magnet directcurrent motor 30 b is mounted on the second mounting bracket 11 b. Asshown in FIG. 5, the first permanent magnet direct current motor 30 ahas the first motor shaft 32 a, and the second permanent magnet directcurrent motor 30 b has the second motor shaft 32 b. The first motorshaft 32 a of the first permanent magnet direct current motor 30 a iscoupled with an arm of the first arm assembly 13 a, and the second motorshaft 32 b of the second permanent magnet direct current motor 30 b iscoupled with an arm of the second arm assembly 13 b.

As shown in FIG. 6, the vehicle step apparatus 100 further includes afirst connection shaft 80 a and a second connection shaft 80 b. Thefirst connection shaft 80 a is coupled with both the first motor shaft32 a and the first arm assembly 13 a, and the second connection shaft 80b is coupled with the second motor shaft 32 b and the second armassembly 13 b. In other words, first motor shaft 32 a is coupled withthe first arm assembly 13 a via a first connection shaft 80 a, and thesecond motor shaft 32 b is coupled with the second arm assembly 13 b viaa second connection shaft 80 b.

Alternatively, the first extending and retracting device 10 a isconfigured in the form of four-link mechanism 10 a 1, five-linkmechanism 10 a 2 or six-link mechanism 10 a 3, and the second extendingand retracting device 10 b is configured in the form of the four-linkmechanism 10 a 1, five-link mechanism 10 a 2 or six-link mechanism 10 a3.

It can be understood that a structure of the second extending andretracting device 10 b may be the same as that of the first extendingand retracting device 10 a. Thus, the first extending and retractingdevice 10 a will be described below, and the second extending andretracting device 10 b will be omitted here.

In an embodiment shown in FIG. 2, the first extending and retractingdevice 10 a is in the form of four-link mechanism 10 a 1, and includesthe first mounting bracket 11 a, the first step bracket 12 a and thefirst arm assembly 13 a. The first arm assembly 13 a is coupled betweenthe first mounting bracket 11 a and the first step bracket 12 a, andincludes a first arm 131 and a second arm 132.

A first end (an upper end) of the first arm 131 is pivotally coupledwith the first mounting bracket 11 a via a first connection pin 136, anda second end (a lower end) of the first arm 131 is pivotally coupledwith the first step bracket 12 a via a second connection pin 137. Afirst end (an upper end) of the second arm 132 is pivotally coupled withthe first mounting bracket 11 a via a third connection pin 138, and asecond end (a lower end) of the second arm 132 is pivotally coupled withthe first step bracket 12 a via a fourth connection pin 139.

The first motor shaft 32 a of the first permanent magnet direct currentmotor 30 a is coupled with one of the first arm 131 and the second arm132. Thus, the first motor shaft 32 a drives the one of the first arm131 and the second arm 132 to rotate, thereby drives the first stepbracket 12 a to extend and retract.

In an embodiment shown in FIG. 3, the first extending and retractingdevice 10 a is in the form of five-link mechanism 10 a 2, and includesthe first mounting bracket 11 a, the first step bracket 12 a and thefirst arm assembly 13 a. The first arm assembly 13 a is coupled betweenthe first mounting bracket 11 a and the first step bracket 12 a, andincludes a first arm 131, a second arm 132 and a third arm 133.

A first end (an upper end) of the first arm 131 is pivotally coupledwith the first mounting bracket 11 a via a first connection pin 136, anda second end (a lower end) of the first arm 131 is pivotally coupledwith the first step bracket 12 a via a second connection pin 137. Afirst end (an upper end) of the second arm 132 is pivotally coupled withthe first mounting bracket 11 a via a third connection pin 138, and asecond end (a lower end) of the second arm 132 is pivotally coupled witha first end (an upper end) of the third arm 133 via a fifth connectionpin 140. A second end (a lower end) of the third arm 133 is pivotallycoupled with the first step bracket 12 a via a fourth connection pin139.

The first motor shaft 32 a of the first permanent magnet direct currentmotor 30 a is coupled with one of the first arm 131 and the second arm132. Thus, the first motor shaft 32 a drives the one of the first arm131 and the second arm 132 to rotate, thereby drives the first stepbracket 12 a to extend and retract.

In an embodiment shown in FIG. 4, the first extending and retractingdevice 10 a is in the form of six-link mechanism 10 a 3, and includesthe first mounting bracket 11 a, the first step bracket 12 a and thefirst arm assembly 13 a. The first arm assembly 13 a is coupled betweenthe first mounting bracket 11 a and the first step bracket 12 a, andincludes a first arm 131, a second arm 132, a third arm 133 and a fourtharm 134.

A first end (an upper end) of the first arm 131 is pivotally coupledwith the first mounting bracket 11 a via a first connection pin 136, anda second end (a lower end) of the first arm 131 is pivotally coupledwith the first step bracket 12 a via a second connection pin 137. Afirst end (an upper end) of the second arm 132 is pivotally coupled withthe first mounting bracket 11 a via a third connection pin 138.

A first end (an upper end) of the third arm 133 is pivotally coupledwith a second end (a lower end) of the second arm 132 via a fifthconnection pin 140, and a second end (a lower end) of the third arm 133is pivotally coupled with the first step bracket 12 a via a fourthconnection pin 139. A first end of the fourth arm 134 is pivotallycoupled with both of the second end of the second arm 132 and the firstend of the third arm 133, and a second end of the fourth arm 134 ispivotally coupled with a middle portion of the first arm 131 via a sixthconnection pin 141.

The first motor shaft 32 a of the first permanent magnet direct currentmotor 30 a is coupled with one of the first arm 131 and the second arm132. Thus, the first motor shaft 32 a drives the one of the first arm131 and the second arm 132 to rotate, thereby drives the first stepbracket 12 a to extend and retract.

The vehicle step apparatus according to other embodiments of the presenttechnology will be described with reference to FIG. 7 and FIG. 8. Thedifference between the vehicle step apparatus according to otherembodiments and the above-mentioned vehicle step apparatus 100 will bedescribed in detail.

In some other embodiments, the vehicle step apparatus 100 includes thefirst extending and retracting device 10 a, the second extending andretracting device 10 b, the step 20, the first permanent magnet directcurrent motor 30 a, the second permanent magnet direct current motor 30b, a first elastic member 50 a and a second elastic member 50 b.

The first elastic member 50 a is configured to elastically deform so asto store energy when the first permanent magnet direct current motor 30a drives the first step bracket 12 a to move towards the first extendedposition, and to release energy so as to assist the first permanentmagnet direct current motor 30 a to drive the first extending andretracting device 10 a, i.e., to drive the first step bracket 12 a, whenthe first permanent magnet direct current motor 30 a drives the firststep bracket 12 a to move towards the first retracted position.

The second elastic member 50 b is configured to elastically deform so asto store energy when the second permanent magnet direct current motor 30b drives the second step bracket 12 b to move towards the secondextended position, and to release energy so as to assist the secondpermanent magnet direct current motor 30 b to drive the second extendingand retracting device 10 b, i.e., to drive the second step bracket 12 b,when the second permanent magnet direct current motor 30 b drives thesecond step bracket 12 b to move towards the second retracted position.

The load of the first permanent magnet direct current motor 30 a duringdriving the step 20 to retract is bigger than that of the firstpermanent magnet direct current motor 30 a during driving the step 20 toextend, so that the working current of the first permanent magnet directcurrent motor 30 a during driving the step 20 to retract is larger thanthat of the first permanent magnet direct current motor 30 a duringdriving the step 20 to extend.

The load of the second permanent magnet direct current motor 30 b duringdriving the step 20 to retract is bigger than that of the secondpermanent magnet direct current motor 30 b during driving the step 20 toextend, so that the working current of the second permanent magnetdirect current motor 30 b during driving the step 20 to retract islarger than that of the second permanent magnet direct current motor 30b during driving the step 20 to extend.

For the vehicle step apparatus, when the step 20 is extending, the firstmotor shaft 32 a drives the first elastic member 50 a to move and thesecond motor shaft 32 b drives the second elastic member 50 b to move.Thus, both the first elastic member 50 a and the second elastic member50 b are caused to be elastically deformed so as to store energy.

When the step 20 is retracting, the first elastic member 50 a releasesenergy to assist the first permanent magnet direct current motor 30 a indriving the first extending and retracting device 10 a, so that the loadand the working current of the first permanent magnet direct currentmotor 30 a are decreased during driving the step 20 to retract. Thesecond elastic member 50 b releases energy to assist the secondpermanent magnet direct current motor 30 b in driving the secondextending and retracting device 10 b, so that the load and the workingcurrent of the second permanent magnet direct current motor 30 b aredecreased during driving the step 20 to retract.

Thus, the working current of the first permanent magnet direct currentmotor 30 a in the processes of driving the step 20 to retract isgenerally consistent with that of the first permanent magnet directcurrent motor 30 a in the processes of driving the step 20 to extend;and the working current of the second permanent magnet direct currentmotor 30 b in the processes of driving the step 20 to retract isgenerally consistent with that of the second permanent magnet directcurrent motor 30 b in the processes of driving the step 20 to extend.Thus, the first permanent magnet direct current motor 30 a and thesecond permanent magnet direct current motor 30 b are protectedeffectively, and the working life of the first permanent magnet directcurrent motor 30 a and that of the second permanent magnet directcurrent motor 30 b are prolonged.

In some embodiments, the first elastic member 50 a includes a firstscroll spring, and the second elastic member 50 b includes a secondscroll spring. A first end 51 a of the first scroll spring is fixed, anda second end 52 a of the first scroll spring is driven by the firstmotor shaft 32 a of the first permanent magnet direct current motor 30 aso as to twist. A first end 51 b of the second scroll spring is fixed,and a second end 52 b of the second scroll spring is driven by thesecond motor shaft 32 b of the second permanent magnet direct currentmotor 30 b so as to twist.

As shown in FIG. 7 and FIG. 8, an end of the outermost ring of the firstscroll spring is bent outwards to form the first end 51 a, and an end ofan innermost ring of the first scroll spring is bent inwards to form thesecond end 52 a. The first end 51 a includes the end of the outermostring of the first scroll spring and a portion of the outermost ringcoupled with the end of the outermost ring. The second end 52 a includesthe end of the innermost ring of the first scroll spring and a portionof the innermost ring coupled with the end of the innermost ring.

An end of the outermost ring of the second scroll spring is bentoutwards to form the first end 51 b, and an end of an innermost ring ofthe second scroll spring is bent inwards to form the second end 52 b.The first end 51 b includes the end of the outermost ring of the secondscroll spring and a portion of the outermost ring coupled with the endof the outermost ring. The second end 52 b includes the end of theinnermost ring of the second scroll spring and a portion of theinnermost ring coupled with the end of the innermost ring.

The first end 51 a of the first scroll spring and the first end 51 b ofthe second scroll spring are fixed with respect to the bracket 11 a andthe bracket 11 b, respectively. When the step 20 is extending, thesecond end 52 a of the first scroll spring rotates along with the firstmotor shaft 32 a and is twisted tightly to store energy, and the secondend 52 b of the second scroll spring rotates along with the second motorshaft 32 b and is twisted tightly to store energy.

When the step 20 is retracting, the second end 52 a of the first scrollspring rotates along with the first motor shaft 32 a and releases energyso as to assist the first permanent magnet direct current motor 30 a todrive the first extending and retracting device 10 a to retract, and thesecond end 52 b of the second scroll spring rotates along with thesecond motor shaft 32 b and releases energy so as to assist the secondpermanent magnet direct current motor 30 b to drive the second extendingand retracting device 10 b to retract.

However, the present technology is not limited to this, both the firstelastic member 50 a and the second elastic member 50 b may be a springleaf, a disk spring or other units or parts easy to be deformedelastically.

As shown in FIG. 7 and FIG. 8, the vehicle step apparatus 100 furtherincludes a first cover 70 a, a first connection plate 60 a, a secondcover 70 b and a second connection plate 60 b.

A first recess 312 a is formed in a first motor casing 31 a of the firstpermanent magnet direct current motor 30 a, and the first cover 70 acovers the first recess 312 a to define a first cavity. The firstconnection plate 60 a is mounted within the first cavity and driven bythe first motor shaft 32 a of the first permanent magnet direct currentmotor 30 a to rotate. The first scroll spring is mounted within thefirst cavity, the first end 51 a of the first scroll spring is fixed inthe first cover 70 a, and the second end 52 a of the first scroll springis coupled with the first connection plate 60 a.

A second recess 312 b is formed in a second motor casing 31 b of thesecond permanent magnet direct current motor 30 b, and the second cover70 b covers the second recess 312 b to define a second cavity. Thesecond connection plate 60 b is mounted within the second cavity anddriven by the second motor shaft 32 b of the second permanent magnetdirect current motor 30 b to rotate. The second scroll spring is mountedwithin the second cavity, the first end 51 b of the second scroll springis fixed in the second cover 70 b, and the second end 52 b of the secondscroll spring is coupled with the second connection plate 60 b.

As shown in FIG. 7 and FIG. 8, the first cover 70 a is detachablyfastened to the first motor casing 31 a of the first permanent magnetdirect current motor 30 a. A first limitation notch 71 a is formed inthe first cover 70 a, a first limitation column 111 a is formed on thefirst mounting bracket 11 a, the first limitation column 111 a is fittedwithin the first limitation notch 71 a to mount the first cover 70 a onthe first mounting bracket 11 a. The first end 51 a of the first scrollspring is fitted over the first limitation column 111 a.

The second cover 70 b is detachably fastened to the second motor casing31 b of the second permanent magnet direct current motor 30 b. A secondlimitation notch 71 b is formed in the second cover 70 b, a secondlimitation column 111 b is formed on the second mounting bracket 11 b,the second limitation column 111 b is fitted within the secondlimitation notch 71 b to mount the second cover 70 b on the secondmounting bracket 11 b. The first end 51 b of the second scroll spring isfitted over the second limitation column 111 b.

Specifically, the first connection plate 60 a is configured as asubstantially circular plate. The first connection plate 60 a isdisposed within the first cavity, and the first connection plate 60 adefines a first surface opposing to the first recess 312 a and a secondsurface opposing to the first cover 70 a. The first connection plate 60a is coupled with the first motor shaft 32 a directly or indirectly, sothat the first connection plate 60 a can rotate under the drive of thefirst motor shaft 32 a. The first scroll spring is fitted over the firstconnection plate 60 a, and the second end 52 a of the first scrollspring is connected to the first connection plate 60 a and rotates alongwith the first connection plate 60 a in a same direction.

The second connection plate 60 b is configured as a substantiallycircular plate. The second connection plate 60 b is disposed within thesecond cavity, and the second connection plate 60 b defines a firstsurface opposing to the second recess 312 b and a second surfaceopposing to the second cover 70 b. The second connection plate 60 b iscoupled with the second motor shaft 32 b directly or indirectly, so thatthe second connection plate 60 b can rotate under the drive of thesecond motor shaft 32 b. The second scroll spring is fitted over thesecond connection plate 60 b, and the second end 52 b of the secondscroll spring is connected to the second connection plate 60 b androtates along with the second connection plate 60 b in a same direction.

Therefore, the first scroll spring and the second scroll spring can beintegrated in the first permanent magnet direct current motor 30 a andthe second permanent magnet direct current motor 30 b respectively so asto decrease transmission loss and make the structure of the vehicle stepapparatus 100 more compactly.

The first connection plate 60 a, the second connection plate 60 b, thefirst cover 70 a, the second cover 70 b, the first recess 312 a and thesecond recess 312 b may have a circular shape or an oval shape.

A number of each of the first limitation notch 71 a, the firstlimitation column 111 a, the second limitation notch 71 b and the secondlimitation column 111 b is not limited to two, and when there are morethan two first limitation notches 71 a and two second limitation notches71 b, the first limitation notches 71 a are provided and evenly spacedapart from each other along a circumferential direction of the firstcover 70 a, and the second limitation notches 71 b are provided andevenly spaced apart from each other along a circumferential direction ofthe second cover 70 b.

A first catch groove 61 a is formed in an outer circumferential surfaceof the first connection plate 60 a, and the second end 52 a of the firstscroll spring is inserted into and fitted within the first catch groove61 a. The first connection plate 60 a is fitted over the firstconnection shaft 80 a and coupled with the first connection shaft 80 avia spline coupling.

A second catch groove 61 b is formed in an outer circumferential surfaceof the second connection plate 60 b, and the second end 52 b of thesecond scroll spring is inserted into and fitted within the second catchgroove 61 b. The second connection plate 60 b is fitted over the secondconnection shaft 80 b and coupled with the second connection shaft 80 bvia spline coupling.

As shown in FIG. 7, the first catch groove 61 a extends along a radialdirection of the first connection plate 60 a, and the second catchgroove 61 b extends along a radial direction of the second connectionplate 60 b. A center of each of the first connection plate 60 a, thefirst motor shaft 32 a, the second connection plate 60 b and the secondmotor shaft 32 b has a spline hole. Each of the first connection shaft80 a and the second connection shaft 80 b has an external spline.

The first motor shaft 32 a drives the first connection shaft 80 a andthe first connection plate 60 a to rotate, and the second end 52 a ofthe first scroll spring fixed on the first connection plate 60 a rotatesalong with the first connection plate 60 a. The second motor shaft 32 bdrives the second connection shaft 80 b and the second connection plate60 b to rotate, and the second end 52 b of the second scroll springfixed on the second connection plate 60 b rotates along with the secondconnection plate 60 b.

Thus, the first scroll spring and the second scroll spring are graduallyrolled up tightly, thus resulting in a simple and compact structure. Inaddition, the first connection shaft 80 a is coupled with the firstmotor shaft 32 a and the first connection plate 60 a via splineconnection so as to ensure driving force transmission and makeinstallation and disassembly to be easy, and the second connection shaft80 b is coupled with the second motor shaft 32 b and the secondconnection plate 60 b via spline connection so as to ensure drivingforce transmission and make installation and disassembly to be easy.

As shown in FIG. 7, a first mounting hole 311 a is formed in the firstmotor casing 31 a, and the first limitation column 111 a is passedthrough the first mounting hole 311 a. A first threaded hole 1111 a isformed in the first limitation column 111 a, and the first permanentmagnet direct current motor 30 a is mounted on the first mountingbracket 11 a via a first bolt 90 a fitted within the first threaded hole1111 a.

A second mounting hole 311 b is formed in the second motor casing 31 b,and the second limitation column 111 b is passed through the secondmounting hole 311 b. A second threaded hole 1111 b is formed in thesecond limitation column 111 b, and the second permanent magnet directcurrent motor 30 b is mounted on the second mounting bracket 11 b via asecond bolt 90 b fitted within the second threaded hole 1111 b.

The first limitation column 111 a is passed through the first limitationnotch 71 a and bears against the first motor casing 31 a. The firstmounting hole 311 a of the first motor casing 31 a is opposite to thefirst threaded hole 1111 a of the first limitation column 111 a. Thefirst bolt 90 a is passed through the first mounting hole 311 a and isfitted within the first threaded hole 1111 a so as to mount the firstmotor casing 31 a to the first mounting bracket 11 a.

The second limitation column 111 b is passed through the secondlimitation notch 71 b and bears against the second motor casing 31 b.The second mounting hole 311 b of the second motor casing 31 b isopposite to the second threaded hole 1111 b of the second limitationcolumn 111 b. The second bolt 90 b is passed through the second mountinghole 311 b and is fitted within the second threaded hole 1111 b so as tomount the second motor casing 31 b to the second mounting bracket 11 b.

Some example embodiments in accordance with the disclosed vehicle stepapparatus are described below.

In an example embodiment in accordance with the present technology(example A1), a motorized step for a vehicle includes a first extendingand retracting device comprising a first mounting bracket attachable toa chassis of a vehicle, a first step bracket, and a first arm assemblycoupled to the first mounting bracket and the first step bracket andconfigured to drive the first step bracket to move between a firstextended position and a first retracted position; a second extending andretracting device comprising a second mounting bracket attachable to thechassis of the vehicle, a second step bracket, and a second arm assemblycoupled to the second mounting bracket and the second step bracket andconfigured to drive the second step bracket to move between a secondextended position and a second retracted position, wherein the secondextended position is aligned with the first extended position, andwherein the second retracted position is aligned with the firstretracted position; a step coupled to the first step bracket and thesecond step bracket; a first permanent magnet direct current motorcoupled with the first arm assembly to drive the first arm assembly; anda second permanent magnet direct current motor coupled with the secondarm assembly to drive the second arm assembly, wherein the firstpermanent magnet direct current motor and the second permanent magnetdirect current motor are configured to drive the first arm assembly andthe second arm assembly, respectively, in unison and with synchronizedmotion as the step extends and retracts.

Example A2 includes the motorized vehicle step of example A1, whereinthe first permanent magnet direct current motor comprises a first motorshaft that is coupled with a first connection shaft of the first armassembly, and wherein the second permanent magnet direct current motorcomprises a second motor shaft that is coupled with a second connectionshaft of the second arm assembly.

Example A3 includes the motorized vehicle step of example A2, includinga first elastic member configured to elastically deform so as to storeenergy when the first permanent magnet direct current motor drives thefirst step bracket to move towards the first extended position, and torelease energy so as to assist the first permanent magnet direct currentmotor to drive the first extending and retracting device when the firstpermanent magnet direct current motor drives the first step bracket tomove towards the first retracted position; and a second elastic memberconfigured to elastically deform so as to store energy when the secondpermanent magnet direct current motor drives the second step bracket tomove towards the second extended position, and to release energy so asto assist the second permanent magnet direct current motor to drive thesecond extending and retracting device when the second permanent magnetdirect current motor drives the second step bracket to move towards thesecond retracted position.

Example A4 includes the motorized vehicle step of example A3, whereinthe first elastic member comprises a first spring defining a fixed firstend and a second end driven by the first motor shaft of the firstpermanent magnet direct current motor so as to change shape; wherein thesecond elastic member comprises a second spring defining a fixed firstend and a second end driven by the second motor shaft of the secondpermanent magnet direct current motor so as to change shape.

Example A5 includes the motorized vehicle step of example A4, whereinthe first spring and the second spring each include one of a scrollspring, a spring leaf, or a disk spring.

Example A6 includes the motorized vehicle step of example A4, whereinthe first spring includes a first scroll spring, and the second springincludes a second scroll spring, the motorized vehicle step furtherincluding a first cover and a first connection plate, wherein a firstrecess is formed in a casing of the first permanent magnet directcurrent motor, and the first cover covers the first recess to define afirst cavity, the first connection plate is mounted within the firstcavity and driven by the first motor shaft of the first permanent magnetdirect current motor to rotate, wherein the first scroll spring ismounted within the first cavity, the first end of the first scrollspring is fixed in the first cover, and the second end of the firstscroll spring is coupled with the first connection plate; and a secondcover and a second connection plate, wherein a second recess is formedin a casing of the second permanent magnet direct current motor, and thesecond cover covers the second recess to define a second cavity, thesecond connection plate is mounted within the second cavity and drivenby the second motor shaft of the second permanent magnet direct currentmotor to rotate, wherein the second scroll spring is mounted within thesecond cavity, the first end of the second scroll spring is fixed in thesecond cover, and the second end of the second scroll spring is coupledwith the second connection plate.

Example A7 includes the motorized vehicle step of example A1, whereinthe first extending and retracting device includes a four-linkmechanism, where the first arm assembly includes a first arm defining afirst end pivotally coupled with the first mounting bracket, and asecond end pivotally coupled with the first step bracket; and a secondarm defining a first end pivotally coupled with the first mountingbracket, and a second end pivotally coupled with the first step bracket,wherein the first permanent magnet direct current motor is coupled withone of the first arm or the second arm.

Example A8 includes the motorized vehicle step of example A1, whereinthe first extending and retracting device includes a five-linkmechanism, where the first arm assembly includes a first arm defining afirst end pivotally coupled with the first mounting bracket, and asecond end pivotally coupled with the first step bracket; a second armdefining a first end pivotally coupled with the first mounting bracket,and a second end; and a third arm defining a first end pivotally coupledwith the second end of the second arm, and a second end pivotallycoupled with the first step bracket, wherein the first permanent magnetdirect current motor is coupled with one of the first arm or the secondarm.

Example A9 includes the motorized vehicle step of example A1, whereinthe first extending and retracting device includes a six-link mechanism,where the first arm assembly includes a first arm defining a first endpivotally coupled with the first mounting bracket, and a second endpivotally coupled with the first step bracket; a second arm defining afirst end pivotally coupled with the first mounting bracket, and asecond end; a third arm defining a first end pivotally coupled with thesecond end of the second arm, and a second end pivotally coupled withthe first step bracket; and a fourth arm defining a first end pivotallycoupled with both of the second end of the second arm and the first endof the third arm, and a second end pivotally coupled with a middleportion of the first arm, wherein the first permanent magnet directcurrent motor is coupled with one of the first arm or the second arm.

Example A10 includes the motorized vehicle step of example A1, whereinthe first permanent magnet direct current motor is coupled to the firstmounting bracket, and the second permanent magnet direct current motoris coupled to the second mounting bracket.

Example A11 includes the motorized vehicle step of example A1, whereinthe first permanent magnet direct current motor and the second permanentmagnet direct current motor are operable to self-lock.

Example A12 includes the motorized vehicle step of example A1, whereinthe first permanent magnet direct current motor and the second permanentmagnet direct current motor are operable to drive the first arm assemblyand the second arm assembly, respectively, at rotational speed that isrelated to a load, such that the rotational speed will be decreased dueto an increasing load and the rotational speed will be increased due toa decreasing load.

In an example embodiment in accordance with the present technology(example A13), a motorized step for a vehicle includes a dual drivemechanism assembly, comprising a first extending and retracting deviceand a second extending and retracting device, the first extending andretracting device comprising a first mounting bracket attachable to achassis of a vehicle, a first step bracket, and a first arm assemblycoupled to the first mounting bracket and the first step bracket andconfigured to drive the first step bracket to move between a firstextended position and a first retracted position, the second extendingand retracting device comprising a second mounting bracket attachable tothe chassis of the vehicle, a second step bracket, and a second armassembly coupled to the second mounting bracket and the second stepbracket and configured to drive the second step bracket to move betweena second extended position and a second retracted position, wherein thesecond extended position is aligned with the first extended position,and wherein the second retracted position is aligned with the firstretracted position; a step coupled to the first step bracket and thesecond step bracket; and a dual motor assembly comprising a first motorand a second motor, the first motor coupled with the first arm assemblyto drive the first arm assembly, and the second motor coupled with thesecond arm assembly to drive the second arm assembly, wherein the dualmotor assembly is operable to cause the step to extend and retract in abalanced orientation where neither side of the step is drooping withrespect to the other based on the first motor and the second motorconfigured to drive the first arm assembly and the second arm assembly,respectively, in unison and with synchronized motion.

Example A14 includes the motorized vehicle step of example A13, whereinthe dual drive mechanism assembly includes a four-link mechanism for oneor both of the first extending and retracting device and the secondextending and retracting device, wherein the four-link mechanismincludes a first arm defining a first end to pivotally couple with amounting bracket of the dual drive mechanism assembly, and a second endto pivotally couple with a step bracket of the dual drive mechanismassembly; and a second arm defining a first end to pivotally couple withthe mounting bracket, and a second end to pivotally couple with the stepbracket, wherein one of the first arm or the second arm is coupled witha motor of the dual motor assembly.

Example A15 includes the motorized vehicle step of example A13, whereinthe dual drive mechanism assembly includes a five-link mechanism for oneor both of the first extending and retracting device and the secondextending and retracting device, wherein the five-link mechanismincludes a first arm defining a first end to pivotally couple with amounting bracket of the dual drive mechanism assembly, and a second endto pivotally couple with a step bracket of the dual drive mechanismassembly; a second arm defining a first end to pivotally couple with themounting bracket, and a second end; and a third arm defining a first endpivotally coupled with the second end of the second arm, and a secondend to pivotally couple with the step bracket, wherein one of the firstarm or the second arm is coupled with a motor of the dual motorassembly.

Example A16 includes the motorized vehicle step of example A13, whereinthe dual drive mechanism assembly includes a six-link mechanism for oneor both of the first extending and retracting device and the secondextending and retracting device, wherein the six-link mechanism includesa first arm defining a first end to pivotally couple with a mountingbracket of the dual drive mechanism assembly, and a second end topivotally couple with a step bracket of the dual drive mechanismassembly; a second arm defining a first end to pivotally couple with themounting bracket, and a second end; a third arm defining a first endpivotally coupled with the second end of the second arm, and a secondend to pivotally couple with the step bracket; and a fourth arm defininga first end pivotally coupled with both of the second end of the secondarm and the first end of the third arm, and a second end pivotallycoupled with a middle portion of the first arm, wherein one of the firstarm or the second arm is coupled with a motor of the dual motorassembly.

Example A17 includes the motorized vehicle step of example A13, whereinthe first motor includes a first motor shaft that is coupled with afirst connection shaft of the first arm assembly, and wherein the secondmotor comprises a second motor shaft that is coupled with a secondconnection shaft of the second arm assembly.

Example A18 includes the motorized vehicle step of example A17,including a first elastic member configured to elastically deform so asto store energy when the first motor drives the first step bracket tomove towards the first extended position, and to release energy so as toassist the first motor to drive the first extending and retractingdevice when the first motor drives the first step bracket to movetowards the first retracted position; and a second elastic memberconfigured to elastically deform so as to store energy when the secondmotor drives the second step bracket to move towards the second extendedposition, and to release energy so as to assist the second motor todrive the second extending and retracting device when the second motordrives the second step bracket to move towards the second retractedposition.

Example A19 includes the motorized vehicle step of example A18, whereinthe first elastic member comprises a first spring defining a fixed firstend and a second end driven by the first motor shaft of the first motorso as to change shape; wherein the second elastic member comprises asecond spring defining a fixed first end and a second end driven by thesecond motor shaft of the second motor so as to change shape.

Example A20 includes the motorized vehicle step of example A19, whereinthe first spring and the second spring each include one of a scrollspring, a spring leaf, or a disk spring.

In some aspects, a vehicle step apparatus with dual drive motors inaccordance with the disclosed embodiments is described.

Motorized vehicle steps typically must carry substantial loads andtherefore may be made of materials of relatively large weight and size,thereby putting demands on the motor. Conventional motorized vehiclestep devices may include multiple extension-retraction devices coupledto the step with one motor driving one of the extension-retractiondevices. A single drive motor requires high motor performance, whichresults in high manufacturing difficulty and high cost.

Conventional single motor-driven vehicle step devices do not providedurability and reliability of the motorized vehicle step, particularlyafter continuous uses. For example, after a conventional singlemotor-driven vehicle step device is used for a period of time (e.g.,hundreds of extensions and retractions), the driven end of the step maysag relative to the motor-driving end of the step, which can create alarger gap between the driven end of the step and the vehicle body thanthe gap between the driving end of the step and the vehicle body, thusaffecting the appearance and performance of the vehicle step device.Furthermore, when the driven end is not locked by the motor assembly,the failure rate of the motor of the motorized vehicle step is increasedafter the vehicle step vibrates for a long time, and the service life ofthe product is shortened. Yet it is challenging to provide a motorizedvehicle step device that can employ multiple (e.g., two or more) motorsto distribute the drive power for extending and retracting the step thatsufficiently addresses and solves these problems with conventionalsystems.

Disclosed are devices and methods for driving a vehicle step assembly bymultiple (e.g. two or more) motors by a motor assembly capable ofself-locking of the of the vehicle step assembly.

As shown in FIGS. 9-13, a vehicle step apparatus 100′ according toembodiments of the present technology includes a step 20′ and a firstextending and retracting device 10 a′ and a second extending andretracting device 10 b′, which are driven by a first motor assembly 900a and a second motor assembly 900 b, respectively, each capable ofself-locking and sometimes referred to as self-locking motor assemblies.In some embodiments, the first motor assembly 900 a and the second motorassembly 900 b each include a worm mechanism including a worm gear andworm to drive the worm gear based on rotation of the worm rotated by aworm shaft coupled to a motor of the respective motor assembly, wherethe worm is structured to have a lead angle greater than the frictionangle to create a self-locking effect of the respective motor assembly,such that only the motor can drive rotation of the shaft in eitherrotational directions while preventing the shaft from rotation in theother non-driven rotational direction. In this manner, the first motorassembly 900 a and the second motor assembly 900 b are each capable ofself-locking in reversible directions, e.g., reverse self-locking,depending on which direction the motor is driving the worm mechanism.This is illustrated in greater detail in FIGS. 9-13.

FIG. 9 shows a schematic view of the vehicle step apparatus 100′. Thefirst extending and retracting device 10 a′ includes a first mountingbracket 11 a′ that is attachable to the underside of a vehicle (e.g.,chassis), a first step bracket 12 a′ and a first arm assembly 13 a′,where the first arm assembly 13 a′ is coupled between the first mountingbracket 11 a′ and the first step bracket 12 a′ and configured to drivethe first step bracket 12 a′ to move between a first extended positionand a first retracted position. Similarly, the second extending andretracting device 10 b′ includes a second mounting bracket 11 b′ that isattachable to the underside of a vehicle (e.g., chassis), a second stepbracket 12 b′ and a second arm assembly 13 b′, where the second armassembly 13 b′ is coupled between the second mounting bracket 11 b′ andthe second step bracket 12 b′ and configured to drive the second stepbracket 12 b′ to move between a second extended position and a secondretracted position. In operations of the vehicle step apparatus 100′,the respective arm assemblies 13 a′ and 13 b′ of the first extending andretracting device 10 a′ and the second extending and retracting device10 b′ are driven in synchrony such that the respective step brackets 12a′ and 12 b′ are aligned with each other during movement and in thefirst extended position and the second extended position, respectively.

The first self-locking motor assembly 900 a is coupled with an arm ofthe first arm assembly 13 a′ (via a shaft, not shown), and the secondself-locking motor assembly 900 b is coupled with an arm of the secondarm assembly 13 b′ (via a shaft, not shown). The first self-lockingmotor assembly 900 a is able to mount on the first mounting bracket 11a′, and the second self-locking motor assembly 900 b is able to mount onthe second mounting bracket 11 b′.

Each extending and retracting device 10 a′ and 10 b′ of the vehicle stepapparatus 100′ is equipped with a drive motor assembly capable of areverse self-locking functionality based on configuration of the motorassembly. In implementations, for example, after receiving a movementinstruction (e.g., from a controller device), both of the self-lockingmotor assemblies 900 a and 900 b operate synchronously, driving therespective extending and retracting devices 10 a′ and 10 b′ to operateaccording to a predetermined trajectory, thus driving the step 20 tooperate between the extended position and the retracted position. Whenthe respective extending and retracting devices 10 a′ and 10 b′ are inthe retracted state, due to the reverse self-locking function of themotor assembly, the step 20 is located in the retracted position andheld into the position without any further movement, e.g., the step 20does not vibrate or result in sagging or drooping after several usages.For example, the reverse self-locking to maintain the step 20 in theretracted position (without vibrating, sagging or drooping) and theconsistency in movement can occur even after thousands of operations ofthe vehicle step apparatus 100′ to move the step 20 between the extendedand retracted positions.

FIGS. 10 and 11 show diagrams depicting an outside perspective view andan exploded view, respectively, of an example embodiment of theself-locking motor assembly 900. The self-locking motor assembly 900includes a motor 911 and a worm gear 915 (both shown in FIG. 11) thatcollectively are encased in a motor housing 904 and a worm gear casing909. In some examples, the motor 911 can include a DC permanent magnetmotor, like the permanent magnet direct current motor 30 discussedearlier. The motor 911 includes a stator portion and a rotor portion,which the rotor includes a worm 911A at the end of a rotor shaft 911B(shown in FIG. 12), and which the stator of the motor 911 couples to anarmature 906. The worm 911A engages with the teeth of the worm gear 915so as to cause rotation of the worm gear 915 to in turn cause aplanetary wheel drive assembly 920 to rotate, e.g., via interfacebetween a gear box bearing 917 from the worm gear 915 to a planetaryshaft 921 of the planetary wheel drive assembly 920. The worm gear 915is encased within the worm gear casing 909, in which a first opening ofthe worm gear casing 909 can be partially covered by a cover 910. Theplanetary wheel drive assembly 920 is encased within the worm gearcasing 909 on the other side, in which a second opening of the worm gearcasing 909 can be partially covered by a cover 925.

The motor assembly 900 includes the worm gear 915 and the worm reductionmechanism (e.g., worm 911A coupled to the stator of the motor 911 viashaft 911B), which enables the motor assembly to have a reverseself-locking function. In multiple-motorized systems, there is a hiddendanger of each motor operating out of synch, which in the case of thetwo motors in the dual-motor driving mode of vehicle step apparatus100′, could lead to misalignment of the step brackets and result insagging or drooping of the step. The worm gear 915 and worm reductionmechanism 911A can provide the motor assembly 900 with a means tosynchronize two (or more) permanent magnet direct current motors thatdrive components (e.g., arm assemblies 13 a′ and 13 b′) without havingto share a common shaft.

For example, a motor having a high rotating speed has an increased loadand a decreased rotating speed, whereas a motor having a low rotatingspeed has a decreased load and an increased rotating speed. Thus,rotating speeds of the two mechanisms reach dynamic balance, therebyrealizing the motion synchronization of the two mechanisms.

Referring to FIG. 11, additional components of the example embodiment ofthe motor assembly 900 are shown, but it is understood that some ofthese components are not required for providing a self-lockingcapability. As shown in FIG. 11, the example embodiment of theself-locking motor assembly 900 can include a socket 908 coupled to thearmature 906, e.g., which can be attached by hexagon socket head capscrews 907. The socket 908 can be connected to the motor housing 904and/or worm gear casing 909 by a connector 905. The end of the rotor ofmotor 911 (with the worm 911A) can be encased in the worm gear casing909 at worm casing region 909A, in which an opening of the worm casingregion 909A can be secured by adjustment screw assembly 914. The end ofthe rotor can be coupled to a gear box ball bearing 913 and an elasticring 912. The gear box bearing 917 can interface with the planetaryshaft 921 via an O-ring 918 and adjusting washer 919. The planetarywheel drive assembly 920 can include a plurality of planetary gearwheels 920 that interface with the teeth of the planetary output shaft921, and a plurality of planetary axels 923 and an output planet carriercomponent 924. The planetary shaft 921 can be secured by a shaft circlip926.

FIGS. 12 and 13 show partial sectional views of the self-locking motorassembly 900, which shows the interface between a worm reductionmechanism and a worm gear.

In some embodiments, the vehicle step apparatus 100′ can also includethe first elastic member 50 a and the second elastic member 50 b tofurther augment the drive capability of the first motor assembly 900 aand the second motor assembly 900 b, respectively. For example, similarto that shown in FIG. 7, the first elastic member 50 a can be coupledbetween the first mounting bracket 11 a′ and the first motor assembly900 a; and the second elastic member 50 b can be coupled between thesecond mounting bracket 11 b′ and the second motor assembly 900 b. Suchembodiments of the vehicle step apparatus 100′ can include the exampleembodiments discussed above for the first elastic member 50 a and thesecond elastic member 50 b, e.g., such as the embodiments pertaining toa spring leaf, a disk spring or other elastically deformable componentand/or to a cover and/or connection plate.

The disclosed multi-motorized vehicle step device, such as the examplevehicle step apparatus 100′, provide several advantages overconventional retractable steps, including but not limited to: (1) longservice life of the device, e.g., as the multiple (dual) motor drivingmode greatly improves the service life of the product and reduces themotor failure rate; (2) the structure is not prone to sag or droop,e.g., as both motors have a self-locking function (e.g., reversibleself-locking) to prevent detrimental movements in the extended andretracted positions; (3) reduced costs of the motor system, e.g., as thedual motor driving mode reduces the requirements for motor performance,thereby allowing a motor that is more simple in manufacturing and lowerin cost (such that the comprehensive cost of the double motor drivingmode and the single motor driving mode is similar if not equivalent);and (4) the dual motor driving mode is more suitable for vehicles withlonger and heavier steps.

Reference throughout this specification to “an embodiment,” “someembodiments,” “an example,” “a specific example,” or “some examples,”means that a particular feature, structure, material, or characteristicdescribed in connection with the embodiment or example is included in atleast one embodiment or example of the present invention. Theappearances of the phrases throughout this specification are notnecessarily referring to the same embodiment or example of the presentinvention. Furthermore, the particular features, structures, materials,or characteristics may be combined in any suitable manner in one or moreembodiments or examples.

Although explanatory embodiments have been shown and described, it wouldbe appreciated by those skilled in the art that the above embodimentscannot be construed to limit the present invention, and changes,alternatives, and modifications can be made in the embodiments withoutdeparting from spirit, principles and scope of the present invention.

While this patent document contains many specifics, these should not beconstrued as limitations on the scope of any invention or of what may beclaimed, but rather as descriptions of features that may be specific toparticular embodiments of particular inventions. Certain features thatare described in this patent document in the context of separateembodiments can also be implemented in combination in a singleembodiment. Conversely, various features that are described in thecontext of a single embodiment can also be implemented in multipleembodiments separately or in any suitable subcombination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Moreover, the separation of various system components in theembodiments described in this patent document should not be understoodas requiring such separation in all embodiments.

Only a few implementations and examples are described and otherimplementations, enhancements and variations can be made based on whatis described and illustrated in this patent document.

What is claimed is:
 1. A motorized vehicle step apparatus, comprising: afirst extending and retracting device comprising a first mountingbracket attachable to a chassis of a vehicle, a first step bracket, anda first arm assembly coupled to the first mounting bracket and the firststep bracket and configured to drive the first step bracket to movebetween a first extended position and a first retracted position; asecond extending and retracting device comprising a second mountingbracket attachable to the chassis of the vehicle, a second step bracket,and a second arm assembly coupled to the second mounting bracket and thesecond step bracket and configured to drive the second step bracket tomove between a second extended position and a second retracted position,wherein the second extended position is aligned with the first extendedposition, and wherein the second retracted position is aligned with thefirst retracted position; a step coupled to the first step bracket andthe second step bracket; a first motor assembly coupled to the first armassembly and operable to (i) drive the first arm assembly to move thefirst step bracket between the first extended position and the firstretracted position and (ii) retain the first step bracket in theretracted position by a reverse self-locking effect of the first motorassembly, the first motor assembly including a first motor having afirst worm on a first rotatable shaft of the first motor, and a firstworm gear operably coupled to the first worm, wherein rotation of thefirst rotatable shaft during an operation of the first motor causesrotation of the first worm gear in one rotational direction that causesthe first motor assembly to drive the first step bracket, and whereinafter the operation of the first motor the first rotatable shaft isprevented from rotation in the other rotational direction based at leaston the first worm and worm gear to create the reverse self-lockingeffect; and a second motor assembly coupled to the second arm assemblyand operable to (i) drive the second arm assembly to move the secondstep bracket between the second extended position and the secondretracted position and (ii) retain the second step bracket in theretracted position by a reverse self-locking effect of the second motorassembly, the second motor assembly including a second motor having asecond worm on a second rotatable shaft of the second motor, and asecond worm gear operably coupled to the second worm, wherein rotationof the second rotatable shaft during an operation of the second motorcauses rotation of the second worm gear in one rotational direction thatcauses the second motor assembly to drive the second step bracket, andwherein after the operation of the second motor the second rotatableshaft is prevented from rotation in the other rotational direction basedat least on the second worm and worm gear to create the reverseself-locking effect, wherein the first motor assembly and the secondmotor assembly are configured to drive the first arm assembly and thesecond arm assembly, respectively, in unison and with synchronizedmotion as the step extends and retracts.
 2. The apparatus of claim 1,wherein the first motor assembly and the second motor assembly aretogether operable to retain the step in the retracted position withoutdetrimental motion including vibrating.
 3. The apparatus of claim 1,wherein the first motor assembly and the second motor assembly aretogether operable to retain the step in the retracted position without amisalignment of the first step bracket and the second step bracket thatcan result in sagging or drooping of the step.
 4. The apparatus of claim1, wherein the first motor assembly comprises a first planetary wheeldrive assembly operably coupled to the first worm gear; and wherein thesecond motor assembly comprises a second planetary wheel drive assemblyoperably coupled to the second worm gear.
 5. The apparatus of claim 4,wherein: the first planetary wheel drive assembly includes a firstplanetary shaft having gear teeth at one end of the first planetaryshaft, and a first plurality of planetary gear wheels that interfacewith the teeth of the first planetary output shaft, and wherein rotationof the first worm gear causes rotation of the first planetary wheeldrive assembly; and the second planetary wheel drive assembly includes asecond planetary shaft having gear teeth at one end of the secondplanetary shaft, and a second plurality of planetary gear wheels thatinterface with the teeth of the second planetary output shaft, andwherein rotation of the second worm gear causes rotation of the secondplanetary wheel drive assembly.
 6. The apparatus of claim 1, wherein thefirst motor includes a permanent magnet direct current motor coupledwith the first arm assembly to drive the first arm assembly; and thesecond motor includes a second permanent magnet direct current motorcoupled with the second arm assembly to drive the second arm assembly.7. The apparatus of claim 6, comprising: a first elastic memberconfigured to elastically deform so as to store energy when the firstpermanent magnet direct current motor drives the first step bracket tomove towards the first extended position, and to release energy so as toassist the first permanent magnet direct current motor to drive thefirst extending and retracting device when the first permanent magnetdirect current motor drives the first step bracket to move towards thefirst retracted position; and a second elastic member configured toelastically deform so as to store energy when the second permanentmagnet direct current motor drives the second step bracket to movetowards the second extended position, and to release energy so as toassist the second permanent magnet direct current motor to drive thesecond extending and retracting device when the second permanent magnetdirect current motor drives the second step bracket to move towards thesecond retracted position.
 8. The apparatus of claim 7, wherein thefirst elastic member comprises a first spring defining a fixed first endand a second end driven by the first rotatable shaft of the firstpermanent magnet direct current motor so as to change shape; wherein thesecond elastic member comprises a second spring defining a fixed firstend and a second end driven by the second rotatable shaft of the secondpermanent magnet direct current motor so as to change shape.
 9. Theapparatus of claim 8, wherein the first spring and the second springeach include one of a scroll spring, a spring leaf, or a disk spring.10. The apparatus of claim 8, wherein the first spring includes a firstscroll spring, and the second spring includes a second scroll spring,the motorized vehicle step apparatus comprising: a first cover and afirst connection plate, wherein a first recess is formed in a casing ofthe first permanent magnet direct current motor, and the first covercovers the first recess to define a first cavity, the first connectionplate is mounted within the first cavity and driven by the firstrotatable shaft of the first permanent magnet direct current motor torotate, wherein the first scroll spring is mounted within the firstcavity, the first end of the first scroll spring is fixed in the firstcover, and the second end of the first scroll spring is coupled with thefirst connection plate; and a second cover and a second connectionplate, wherein a second recess is formed in a casing of the secondpermanent magnet direct current motor, and the second cover covers thesecond recess to define a second cavity, the second connection plate ismounted within the second cavity and driven by the second rotatableshaft of the second permanent magnet direct current motor to rotate,wherein the second scroll spring is mounted within the second cavity,the first end of the second scroll spring is fixed in the second cover,and the second end of the second scroll spring is coupled with thesecond connection plate.
 11. The apparatus of claim 1, wherein the firstextending and retracting device includes a four-link mechanism, wherethe first arm assembly includes a first arm defining a first endpivotally coupled with the first mounting bracket, and a second endpivotally coupled with the first step bracket; and a second arm defininga first end pivotally coupled with the first mounting bracket, and asecond end pivotally coupled with the first step bracket, wherein thefirst permanent magnet direct current motor is coupled with one of thefirst arm or the second arm.
 12. The apparatus of claim 1, wherein thefirst extending and retracting device includes a five-link mechanism,where the first arm assembly includes a first arm defining a first endpivotally coupled with the first mounting bracket, and a second endpivotally coupled with the first step bracket; a second arm defining afirst end pivotally coupled with the first mounting bracket, and asecond end; and a third arm defining a first end pivotally coupled withthe second end of the second arm, and a second end pivotally coupledwith the first step bracket, wherein the first permanent magnet directcurrent motor is coupled with one of the first arm or the second arm.13. The apparatus of claim 1, wherein the first extending and retractingdevice includes a six-link mechanism, where the first arm assemblyincludes a first arm defining a first end pivotally coupled with thefirst mounting bracket, and a second end pivotally coupled with thefirst step bracket; a second arm defining a first end pivotally coupledwith the first mounting bracket, and a second end; a third arm defininga first end pivotally coupled with the second end of the second arm, anda second end pivotally coupled with the first step bracket; and a fourtharm defining a first end pivotally coupled with both of the second endof the second arm and the first end of the third arm, and a second endpivotally coupled with a middle portion of the first arm, wherein thefirst permanent magnet direct current motor is coupled with one of thefirst arm or the second arm.
 14. The apparatus of claim 1, wherein thefirst motor is attachable to the first mounting bracket, and the secondmotor is attachable to the second mounting bracket.
 15. A motorizedvehicle step apparatus, comprising: a first extending and retractingdevice comprising a first mounting bracket attachable to a chassis of avehicle, a first step bracket, and a first arm assembly coupled to thefirst mounting bracket and the first step bracket and configured todrive the first step bracket to move between a first extended positionand a first retracted position; a second extending and retracting devicecomprising a second mounting bracket attachable to the chassis of thevehicle, a second step bracket, and a second arm assembly coupled to thesecond mounting bracket and the second step bracket and configured todrive the second step bracket to move between a second extended positionand a second retracted position, wherein the second extended position isaligned with the first extended position, and wherein the secondretracted position is aligned with the first retracted position; a stepcoupled to the first step bracket and the second step bracket; a firstmotor assembly coupled to the first arm assembly and operable to drivethe first arm assembly to move the first step bracket between the firstextended position and the first retracted position, the first motorassembly including a first means for reverse self-locking to retain thefirst step bracket in the retracted position, wherein after the firststep bracket is driven to the first retracted position, the first meansfor reverse self-locking prevents a rotation of a first shaft of thefirst means for reverse self-locking in another rotational direction;and a second motor assembly coupled to the second arm assembly andoperable to drive the second arm assembly to move the second stepbracket between the second extended position and the second retractedposition, the second motor assembly a second means for reverseself-locking to retain the second step bracket in the retractedposition, wherein after the second step bracket is driven to the secondretracted position, the second means for reverse self-locking prevents arotation of a second shaft of the second means for reverse self-lockingin another rotational direction, wherein the first motor assembly andthe second motor assembly are configured to drive the first arm assemblyand the second arm assembly, respectively, in unison and withsynchronized motion as the step extends and retracts.
 16. The apparatusof claim 15, wherein the first motor assembly and the second motorassembly are together operable to retain the step in the retractedposition without detrimental motion including vibrating.
 17. Theapparatus of claim 15, wherein the first motor assembly and the secondmotor assembly are together operable to retain the step in the retractedposition without a misalignment of the first step bracket and the secondstep bracket that can result in sagging or drooping of the step.
 18. Theapparatus of claim 15, wherein the first extending and retracting deviceincludes a four-link mechanism, where the first arm assembly includes afirst arm defining a first end pivotally coupled with the first mountingbracket, and a second end pivotally coupled with the first step bracket;and a second arm defining a first end pivotally coupled with the firstmounting bracket, and a second end pivotally coupled with the first stepbracket, wherein the first permanent magnet direct current motor iscoupled with one of the first arm or the second arm.
 19. The apparatusof claim 15, wherein the first extending and retracting device includesa five-link mechanism, where the first arm assembly includes a first armdefining a first end pivotally coupled with the first mounting bracket,and a second end pivotally coupled with the first step bracket; a secondarm defining a first end pivotally coupled with the first mountingbracket, and a second end; and a third arm defining a first endpivotally coupled with the second end of the second arm, and a secondend pivotally coupled with the first step bracket, wherein the firstpermanent magnet direct current motor is coupled with one of the firstarm or the second arm.
 20. The apparatus of claim 15, wherein the firstextending and retracting device includes a six-link mechanism, where thefirst arm assembly includes a first arm defining a first end pivotallycoupled with the first mounting bracket, and a second end pivotallycoupled with the first step bracket; a second arm defining a first endpivotally coupled with the first mounting bracket, and a second end; athird arm defining a first end pivotally coupled with the second end ofthe second arm, and a second end pivotally coupled with the first stepbracket; and a fourth arm defining a first end pivotally coupled withboth of the second end of the second arm and the first end of the thirdarm, and a second end pivotally coupled with a middle portion of thefirst arm, wherein the first permanent magnet direct current motor iscoupled with one of the first arm or the second arm.